[2005][C#]WebRequestで取得したStreamをそのままファイルに保存したい

  WebRequest webReq = WebRequest.Create(strSendURLAll);
  webReq.Timeout = 30 * 1000;
  webReq.Method = HTTP_GET;

  WebResponse webRes = webReq.GetResponse();  
  Stream sr = webRes.GetResponseStream();
  int intBuffSize = 1000;
  int intFileSize = 0;
  FileStream srmSaveFile = new FileStream(pstrSaveFileDirName + pstrGetFileName,
                                          FileMode.Create);


  //nバイトずつ読み込む
  int intRet = 0;
  do
  {
      byte[] bytBuff = new byte[intBuffSize];
      //1000バイトずつ読み込む
      intRet = sr.Read(bytBuff, 0, intBuffSize);
      if (intRet == 0) break;
      //ファイルへ書き込み
      srmSaveFile.Write(bytBuff, 0, intRet);
      intFileSize += intRet;
  }
  while (intRet - intBuffSize >= 0);

  sr.Close();
  srmSaveFile.Close();

int read;

while ((read = stream.Read(buffer, 0, bufferSize)) > 0) {

    //  処理

}